Referring to FIG. 1, a strip of photographic film must convey a significant amount of information to the photofinisher in order to take advantage of certain automated cost-saving features which enable the photofinisher to process the film at a reduced cost. For manually operated photofinishing machines, the top edge of the film includes sufficient eye-readable information to enable the operator to properly print the film. Specifically, in the example of FIG. 1, the eye-readable information on the top edge of the film includes the manufacturer's name, the type of film, the speed of the film, and a number assigned by the film manufacturer designating the type of film. For automated photofinishing machines, a so-called "DX" bar code is provided along the bottom edge of the film between every half frame number. The half frame numbers are, for example, 1, 1A, 2, 2A, etc. The DX bar code, which is between each of these numbers, specifies the National Association of Photographic Manufacturers (NAPM) number (designating the film type) and generation number printed in eye-readable form on the top edge. Automatic photofinishing machines, prior to printing the film, carefully guide the bottom edge of the film past an optical bar code reader in order to extract the information necessary to determine the film type. The DX bar code illustrated in the bottom edge of the film strip in FIG. 1 is printed every half frame in order to avoid such information being lost upon the film strip being notched by a notching machine. Typically, a notching machine places a notch along one edge of the film to delineate frame locations. Thus, a notch will appear along one edge of the film at every frame. If the bottom edge of the film is selected for notching, the notches may make unreadable every other one of the bar code patterns along the bottom edge.
A significant problem exists in reordering prints. A customer must specify to the photofinisher which frame on the strip of film should be reprinted. Thus, the customer must select the correct half frame number. This creates significant ambiguities, particularly in those cases where the customer is unfamiliar with the frame number format of film. Such ambiguities can result in the customer being furnished reprints of the wrong frames. In order to overcome this problem, it has been proposed to provide a bar code with every frame specifying the frame number. The bar code can be automatically read at the time the first print is made so that a frame number is automatically associated with each print made from the strip of film. Such information can be used in order to assure that the customer's desire is always met and to eliminate any potential ambiguities. Such a proposal is illustrated in FIG. 2, and in Japanese patent application No. 63-305337. The DX bar code lies along the bottom edge of the film strip and a frame number bar code lies along the top edge of the film strip at every frame.
As shown in FIG. 2, this presents a problem, in that the eye-readable information along the top edge of the film must be compressed within a smaller area. The disadvantage is that the minilab photofinishing operators must now glean their information from smaller eye-readable characters. An additional problem arises because it is desirable to provide eye-readable half-frame numbers not only along the bottom edge of the film strip but also full-frame numbers along the top edge, as illustrated in FIG. 2. This feature is particularly helpful to manually operated photofinishing equipment, enabling the photofinishing operator to obtain all the necessary information by reading the top edge of the film only. Unfortunately, this feature further reduces the space available for the other eye-readable symbols.
Another disadvantage to the format illustrated in FIG. 2 is that the automated photofinishing lab must have two bar code readers, one for the top edge and one for the bottom edge, adding a significant expense. Moreover, reading bar codes on both opposing edges of the film requires carefully guiding both edges past the two bar code readers. While it is possible to carefully guide one edge of the film past the bar code reader, significant problems are encountered in trying to simultaneously guide both edges of the film past top and bottom bar code readers.
Finally, it is conventional when reprinting the film or in making over poor prints, to mount the film strip in a continuous web, which permits the operator to handle the film strip without touching the film itself. Such a web, as is well-known in the art, covers one of the film edges. In the film strip illustrated in FIG. 2, the operator would have to select one or the other of the two bar codes to be covered up by the web, preventing its being read upon the film being fed into automatic printing apparatus, a significant disadvantage.
One solution to the foregoing problems may be to move all bar codes to one edge of the film, the opposite edge of the film being dedicated to eye-readable information only. Such a technique is illustrated in FIG. 3. In the film strip 300 of FIG. 3, the so-called "DX" bar code 305 is accommodated every half frame while the frame number bar code 310 is accommodated in alternate half frames. This leaves plenty of room along the top edge of the film 300 for the eye-readable information, including the manufacturer's code number, the frame number, the manufacturer's name, the film type, the film speed and the generation. In this example the manufacturer's code number is 5097, the frame number is 4, the manufacturer is Kodak, the film type is Gold, the film speed is 400 and the generation is 1. The solution proposed in FIG. 3 suffers from the significant disadvantage that the DX and frame number bar codes each appear only once each frame. Thus, if the automatic printing machinery notches the film strip 300 along its bottom edge, there is a significant probability that either the DX code bar code or the frame number bar code will be rendered unreadable in every single frame. As mentioned previously, automatic notching machinery typically removes a notch from one edge of the film to delineate the location of each frame. Thus, a notch 315 (illustrated in dashed line in FIG. 3) would render unreadable the DX bar code or, alternatively, would render unreadable the frame number bar code in every frame, depending upon its placement. Thus, the proposed solution of FIG. 3 is really no solution at all.
In summary, the state of the art has been such that one could not provide an automatically readable bar coded frame number on film without suffering from either one of two disadvantages. On the one hand, if the DX bar code and the frame number bar code are placed on opposite edges of the film, a web used for automatic printing of the film during reprint or makeover printing will prevent one or the other of the two bar codes from being read automatically in a large automatic photofinishing machine, a significant disadvantage. On the other hand, if both bar codes are placed along the same edge of the film, then there is not enough room along that one edge in which to provide both bar codes every half frame. Accordingly, notching of that edge of the film by an automatic photofinishing notching device can render unreadable all bar coded frame numbers on that strip of film. Either disadvantage is unacceptable. Accordingly, there is a great need in the art for a way in which to provide machine-readable bar coded frame numbers on the film without suffering from either of the alternative disadvantages discussed above.